Stochastic processes are key determinants of short-term evolution in influenza a virus.

ABSTRACT: Understanding the evolutionary dynamics of influenza A virus is central to its surveillance and control. While immune-driven antigenic drift is a key determinant of viral evolution across epidemic seasons, the evolutionary processes shaping influenza virus diversity within seasons are less clear. Here we show with a phylogenetic analysis of 413 complete genomes of human H3N2 influenza A viruses collected between 1997 and 2005 from New York State, United States, that genetic diversity is both abundant and largely generated through the seasonal importation of multiple divergent clades of the same subtype. These clades cocirculated within New York State, allowing frequent reassortment and generating genome-wide diversity. However, relatively low levels of positive selection and genetic divers

SUBMITTER: Nelson MI 

PROVIDER: S-EPMC1665651 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature